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Klinefelter syndrome (KS) is the most common sex chromosome aneuploidy. A distinctive characteristic of KS is oligozoospermia. Despite multiple studies that have described the natural history of the degenerative process of germ cells in patients with KS, the molecular mechanisms that initiate this process are not well characterized. MicroRNA (miRNA)-mediated post-transcriptional control mechanisms have been increasingly recognized as important regulators of spermatogenesis; however, only a few studies have evaluated the role of miRNAs in the gonadal failure of these patients. Here, we describe a differential expression profile for the miRNAs in testicular tissue samples taken from KS patients. We analysed testicular tissue samples from 4 KS patients and 5 control patients (obstructive azoospermia) through next-generation sequencing, which can provide information about the mechanisms involved in the degeneration of germ cells. A distinctive differential expression profile was identified for 166 miRNAs in the KS patients: 66 were upregulated, and 100 were downregulated. An interactome analysis was performed for 7 of the upregulated and the 20 downregulated miRNAs. The results showed that the target genes are involved in the development, proliferation, and differentiation processes of spermatogenesis, which may explain their role in the development of infertility. This is the first report of a miRNA expression profile generated from testicular tissue samples of KS patients.

Background:Peripheral gene expression of several molecular pathways has been studied in major depressive disorder (MDD) with promising results. We sought to investigate some of these genes in a treatment-free Latino sample of Mexican descent.Material and Methods:The sample consisted of 50 MDD treatment-free cases and 50 sex and age-matched controls. Gene expression of candidate genes of neuroplasticity (BDNF, p11, and VGF), inflammation (IL1A, IL1B, IL4, IL6, IL7, IL8, IL10, MIF, and TNFA), the canonical Wnt signaling pathway (TCF7L2, APC, and GSK3B), and mTOR, was compared in cases and controls. RNA was obtained from blood samples. We used bivariate analyses to compare subjects versus control mean mRNA quantification of target genes and lineal regression modelling to test for effects of age and body mass index on gene expression.Results:Most subjects were female (66%) with a mean age of 26.7 (SD 7.9) years. Only GSK3B was differentially expressed between cases and controls at a statistically significant level (p = 0.048). TCF7L-2 showed the highest number of correlations with MDD-related traits, yet these were modest in size.Discussion:GSK3B encodes a moderator of the canonical Wnt signaling pathway. It has a role in neuroplasticity, neuroprotection, depression, and other psychiatric phenotypes. We found that adding population diversity has the potential to elicit distinct peripheral gene expression markers in MDD and MDD-related traits. However, our results should only be considered as hypothesis-generating research that merits further replication in larger cohorts of similar ancestry.

Background: DNA methylation is the best epigenetic mechanism for explaining the interactions between nutrients and genes involved in intrauterine growth and development programming. A possible contributor of methylation abnormalities to congenital heart disease is the folate methylation regulatory pathway, however, the mechanisms and methylation patterns of VSD-associated genes are not fully understood. Objective: To determine if maternal dietary intake of folic acid (FA) is related to the methylation status (MS) of VSD-associated genes (AXIN1, MTHFR, TBX1, and TBX20). Methods: Prospective case–control study, 48 mothers and their children were evaluated. The mothers’ dietary variables were collected through a food frequency questionnaire focusing on FA and the consumption of supplements with FA. The MS of promoters of genes was determined in the children. Results: The intake of FA supplements was significantly higher in the control mothers. In terms of maternal folic acid consumption, significant differences were found in the first trimester of pregnancy. Significant differences were observed in the MS of MTHFR and AXIN1 genes in VSD and control children. A correlation between maternal FA supplementation and MS of AXIN1 and TBX20 genes was found in control and VSD children, respectively. Conclusions: A lower MS of AXIN1 genes and a higher MS of TBX20 genes is associated with FA maternal supplementation.

Background: Triple negative breast cancer (TNBC) presents a very aggressive behavior with a high rate of metastasis. Overexpression of HMGA1 has been reported in TNBC and has been associated with the induction of the Epithelial-Mesenchymal transition (EMT) and metastasis. Therefore, HMGA1 is considered a master regulator of tumor progression in TNBC. The objective of this work was to know which genes are directly or indirectly regulated by HMGA1 to better understand their participation in EMT and their role in aggressive TNBC. Methods: We performed the silencing of the HMGA1 gene using siRNA Silencer® Select Pre-designed (s6667 HMGA1, 4390849 GAPDH, 4390843 Negative control, all from Thermo Fisher, MA, USA) in two TNBC cell lines, HCC-1395 and MDA-MB-231, and we observed the effect of this gene inhibition by microarray global expression analysis using GeneChip Human Genome U133 Plus 2.0 (Affymetrix, CA, USA), comparing the conditions of inhibition versus their own control without inhibition. After the microarray data mining, results for the HMGA1 and PRRX1 genes were validated by qPCR using the Prime Time® Primers for HMGA1 (Hs.PT.58.38699366), PRRX1 (Hs.PT.58.2820749), and GAPDH as endogenous gene (Hs.PT.39a.22214836) with SybrGreen reagent (Roche, Basel, Switzerland). The level of expression of the HMGA1 and PRRX1 proteins was analyzed by Western blot in nuclear protein extracts of each cell line before and after gene silencing. Finally, we performed an in silico analysis using the "Gene 2 promoter" tool in the Genomatix platform to search the promoters and binding proteins of the PRRX1 gene. Results: The silencing of HMGA1 in a non-metastatic TNBC-cell line, HCC-1395, showed deregulation of genes associated with cell proliferation and angiogenesis. Meanwhile the silencing in a TNBC-metastatic cell line, MDA-MB-231, resulted in the deregulation of genes involved in the formation and organization of the cytoskeleton, including the overexpression of PRRX1. Validation of the expression changes of HMGA1 and PRRX1 by qPCR and Western blot was performed and HMGA1 was confirmed to negatively regulate the PRRX1 gene expression. Through in silico studies, we identified several binding sites of HMGA1 to the PRRX1 promoter. Conclusions: The subexpression of PRRX1 is necessary for EMT to occur. In this study, we present the interesting finding that HMGA1 regulates the subexpression of PRRX1, as supported by the experiments of transcriptional and translational expression presented in this work. To our knowledge, this is the first report describing a regulatory role of HMGA1 on PRRX1, which could explain the metastatic capacity of cancers that overexpress HMGA1. Key words: Epithelial-Mesenchymal Transition, Triple Negative Breast Cancer, Mesenchymal-Epithelial Transition, Metastasis. Citation Format: Aguayo-Millán CD, Santuario-Facio SK, Treviño-Alvarado V, Calvo-Anguiano G, Rojas-Martínez A, Camacho-Morales A, Ortíz-López R. HMGA1 negatively regulates the expression of PRRX1 in triple negative breast cancer cells, which favors the progression to metastasis [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-08-04.

Summary Background Genitourinary disorders are the most frequent congenital defects in newborns; however, little is known about their etiology. Several studies have been carried out to find genetic risk factors in the development of these malformations. The expression of VAMP7 is found in testes, epididymis, seminal vesicles, prostatic tissues, penis, and urethra. Alterations in gene dose of VAMP7 were recently reported in a subset of male patients initially identified clinically by the presence of congenital genitourinary disorders. In 2016, the authors developed a diagnostic algorithm for early detection of sex chromosome aneuploidies by quantifying the SHOX, VAMP7, and SRY gene dose in newborns by qPCR using dried blood spot (DBS) samples. Objective Correlate the increased gene dose of VAMP7, obtained by qPCR using DBS, with genitourinary congenital defects attributable to disorders in virilization and verify the increased gene dose by microarrays. Study design Samples that only presented increased VAMP7 gene dosage were selected from a previously analyzed group of 5088 males in which the early detection of sex chromosomes aneuploidies was performed. Eight males were found with an increased gene dose of VAMP7 (relative quantitation > 1.3) and were called in for a complete clinical evaluation aimed at the identification of genitourinary anomalies, qPCR and microarrays. Results Eight males from 5088 samples were identified with increased VAMP7 gene dosage of which six patients were clinically evaluated, of which 50% were identified with alterations in genital development (bilateral cryptorchidism, unilateral cryptorchidism, and glandular hypospadias) and speech delay, while the rest presented different types of atopy. Discussion Tannour-Louet et al. postulated on 2014 that the duplication of the Xq28 region, specifically of VAMP7, plays a role in the human masculinization disorders of the urogenital tract. The study was based on array comparative genomic hybridization (aCGH) results performed to 116 males with disorders of sexual differentiation. In the present study, the patients were initially selected due to an increased gene dose of VAMP7 detected by qPCR, then the clinical evaluation and the aCGH were performed, inverse to what was reported previously but with similar percentages between both studies. Conclusion In this work, the authors report cases of cryptorchidism, hypospadias, language delay and atopy in male preschoolers initially identified because they have an increased gene dose of VAMP7.

Introduction Molecular analysis in haemophilia is currently used in the diagnosis, treatment and prognosis of this disease. Hispanic populations in Latin America have been of interest to researchers due to the reportedly high prevalence of inhibitors in these patients. Aim To perform next-generation sequencing (NGS) in a cohort of Mexican patients with HA and HB and correlate with clinical phenotypes. Methods Patients with Haemophilia A (HA) or haemophilia B (HB), were evaluated using NGS with an Ion AmpliSeq Custom Panel. Odds ratios (ORs) for associations between F8 variants and inhibitors were obtained. Results A total of 85 patients (60 with HA and 25 with HB) were included. Pathogenic variants in F8 were found in 93.3% of HA patients and in F9 in 96% of HB patients. Twelve novel potentially pathogenic variants were found. Inhibitors were observed in 20% of patients with severe HA. Four patients clinically diagnosed with HA were negative for F8 variants. Conclusion Overall detection rate of pathogenic variants in F8 and F9 genes was 94.6%. We identified 12 non previously reported variants and pathogenic variants in other coagulation related genes. Molecular diagnosis of HA and HB permits better options for management, assessment and genetic counseling.